"Operation not permitted" error

[allenzyq]

I fllow you tips to copy code by iTem. but first step was wrong. The message was
ERROR: While executing gem ... (Errno::EPERM)
Operation not permitted - /usr/bin/cdiff

[UnderMistake]

@allenzyq you need to executebrew install ruby

[inket]

Can't reproduce this error. Tried with system ruby too. Any more information that could help with identifying the problem and fixing it?

[tylerlie]

use this command : sudo gem install -n /usr/local/bin update_xcode_plugins